1. Fields of the Invention
The present invention relates to a valve unit (F16K-005/06), and more particularly, to a positioning device for a knob of the valve unit so that when rotating the knob, at least one sound is generated and the knob is well positioned.
2. Descriptions of Related Art
The conventional piping system for delivering fluid generally has at least one valve unit which is able to regulate the unit volume or pressure of the fluid in the piping system. A knob is located on outside of the valve unit and has an inner threaded portion so as to be connected to the outer threaded portion of the body of the valve. When rotating the knob, a plate in the valve unit can be moved to achieve the function of regulating the unit volume or pressure of the fluid in the piping system.
When finishing the regulation process, the knob has to be secured so as to prevent the knob from loosening.
As shown in FIG. 10, a conventional positioning device for a knob is disclosed and includes an external pin 8 which extends through the valve 6 and is inserted into one of the holes 61 of the knob 7, such that the knob 7 is well positioned.
As shown in FIG. 11, another conventional positioning device for a knob is disclosed, wherein the knob 7 has a nut 9 located at the underside thereof. The nut 9 is threadedly connected to the outer threaded portion of the valve 6. The nut 9 is securely connected to the knob 7 by using a wrench to tighten the nut 9, such that the knob 7 is well positioned.
However, the external pin 8 protrudes outward, and the nut 9 has to be tightened by using a wrench. These conventional ways are not convenient.
The present invention intends to provide a positioning device for a knob of the valve unit so as to eliminate the shortcomings mentioned above.